1. Field of Invention
The present invention relates to a knob structure, and particularly to a knob structure applied in an electronic device, wherein a preset control signal is input by rotating the knob structure.
2. Related Art
With the rapid popularity of multimedia technologies and applications, more and more types of portable electronic devices are appearing, such as mobile telephones, personal digital assistants (PDA), digital cameras, MP3 players, MPEG4 players, recording digital photo frames, and handheld game players. Further, with continuous advancement of science and technology, those portable electronic devices are becoming smaller in volume to be carried more conveniently by users and more powerful in function to satisfy their requirements.
Regarding the MP3 player which is quite popular at present, the MP3 player comprises a main part at least comprising a display screen and a plurality of keys, wherein the display screen is used to display a list of songs, and a series of actions, such as enter, play, forward, and backward, may be performed through the keys. A user may operate the MP3 player more conveniently if there are more keys, but the volume of the MP3 player will become larger. On the other hand, if the number of the keys is small, though the volume of the MP3 player may be reduced, many operations will need to be performed by pressing two or three keys simultaneously, which complicates operation for the user.
In order to solve the problem that volume and convenience of operation conflict with each other, an electronic touch knob is applied in an iPod player introduced by Apple Computer Inc. The user may rotate the touch knob to send a corresponding preset command, and by using a menu operation interface, the user may conveniently perform actions such as enter, play, forward, or backward conveniently. The user may also use the touch knob to adjust sound volume. Through the design of the touch knob, the iPod can not only perform various functions easily, but also has a reasonably small volume. Through the design of the touch knob of the iPod, the user may rotate and slide the knob in a corresponding region in the body by a finger, which lacks the touch feeling the user may have when pressing the keys. In order to show response to the action of the user, a buzzer is added into the electrical part of the iPod and displayed through the display screen.
Similarly, in order to solve the problem that the convenience of operation and the volume conflict with each other, besides that the iPod employs the electronic touch knob, a mechanical knob structure may be disposed in the MP3 player. For example, a rotary component has been disclosed in Japan Patent No. 2000297077. The rotary component comprises a cabinet and a rotary body, wherein the rotary body may rotate on the cabinet and output a control signal. Referring to FIG. 1, it is a schematic view of a rotary component 41 applied in a MP3 player 53. A rotary wheel 42 is fixedly combined with the rotary component 41, and a through-hole 531 is perforated in the body case of the MP3 player 53 corresponding to the position of the rotary wheel 42. After the rotary component 41 and the rotary wheel 42 are installed on a circuit board 532 of the MP3 player 53, the through-hole of the body case is covered corresponding to the rotary wheel 42. Since a flange is disposed between the cabinet of the rotary component 41 and the rotary body, the user will feel fragmental tactility through the flange when operating the rotary wheel 42 to drive the rotary body to rotate. As such, the user may know whether the operation is performed through the physical tactility, so the buzzer demanded by the electronic touch knob is unnecessary.
For the MP3 player adopting the rotary component, during the practical production and assembly, the rotary component and the rotary wheel are firstly assembled on the circuit board and locked with the body case together. Among the rotary component, the rotary wheel, the through-hole in the body case, and the body itself has dimensional errors, and the dimensional errors are summed up when the components are assembled. The rotary wheel and the through-hole of the body will interfere with each other easily due to dimensional errors. As such, the user may feel it is inconvenient to operate due to the interference, and if the interference is serious, the MP3 player will be determined to be scraped.
Furthermore, the aforementioned rotary wheel does not have the function of light indication, so it is difficult for the user to operate when light is insufficient or at night. Further, at present, keys of a mobile phone are provided with a backlight source and when the user presses a press key, the backlight source is triggered to illuminate the position of the press key, such that the user can use the mobile phone conveniently. However, for the aforementioned rotary wheel, the luminescent design cannot be adopted due to the aforementioned interference.